JP2009086153A - Charged particle movement-type display panel, method for fabricating charged particle movement-type display panel, and charged particle movement-type display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a charged particle movement-type display panel, easily producing a narrow rib and extending a display area of a transparent substrate to improve resolution and visibility. <P>SOLUTION: The charged particle movement-type display panel 1 comprises a transparent substrate 10, a backside substrate 20 disposed opposing to the transparent substrate 10, and a display liquid 40 sealed between the transparent substrate 10 and the backside substrate 20 and including charged particles. The display panel 1 further comprises a first rib 31 provided on the transparent substrate 10 so as to project toward the backside substrate 20 and a second rib 32 provided on the backside substrate 20 so as to project toward the transparent substrate 10. The first rib 31 has a joint 31b connected to the transparent substrate 10 and at least having a width L1 narrower than the width L2 of the second rib 32, and a height H1 lower than the height H2 of the second rib 32. The device further comprises a black matrix 41B including black charged particles held between a protruding surface 31a of the first rib 31 and a protruding surface 32a of the second rib 32. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a charged particle movement type display panel in which charged particles are sealed between a transparent substrate and a back substrate, a method for manufacturing a charged particle movement type display panel, and a charged particle movement type display device, and more particularly, a narrowed partition wall. Can be manufactured easily, the display area of the transparent substrate can be expanded, the resolution can be increased and the visibility can be improved, the charged particle movement type display panel, the charged particle movement type display panel manufacturing method, and the charged particle movement type The present invention relates to a display device.

  2. Description of the Related Art Conventionally, research and development of display panels that employ a charged particle movement method (hereinafter simply referred to as “charged particle movement type display panels”) have been performed as image display devices such as portable terminals and electronic paper. For example, in the case of a charged particle migration type display panel having an active matrix structure, a transparent substrate to which a common electrode is attached, a back substrate to which a plurality of pixel electrodes are attached, and a partition disposed between the transparent substrate and the back substrate In a region defined by the transparent substrate, the back substrate, and the partition walls, for example, dark charged particles such as black and light charged particles such as white are sealed. Then, by applying a predetermined voltage to each pixel electrode to generate an electric field between the rear substrate and the transparent substrate, dark or light colored charged particles are moved to the transparent substrate side to display black, white or gray, etc. I do.

  In order to improve the resolution of such a charged particle migration type display panel, the partition area partitioning each pixel is narrowed to enlarge the display area of the transparent substrate. Specifically, the display area of the transparent substrate has been enlarged by making the end width of the partition wall on the transparent substrate side into a substantially tapered (trapezoidal) cross section shorter than the end width on the back substrate side.

For example, Japanese Patent Laid-Open No. 2003-208107 (Patent Document 1) describes a ratio (a / b) between an end width a on the transparent substrate side and an end width b on the back substrate side in the partition wall cross section as 0.1. A charged particle migration type display panel having a configuration of 8 or less is disclosed. Japanese Patent Laying-Open No. 2004-20640 (Patent Document 2) discloses a charged particle migration type display panel having a configuration in which the bonding area of the partition walls on the transparent substrate side is smaller than the bonding area on the rear substrate side.
JP 2003-208107 A JP 2004-20640 A

  However, since the partition walls of the above-described conventional charged particle migration type display panel are both substantially tapered in cross section, the end width a on the transparent substrate side is narrower than the end width b on the back substrate side. The ratio between the height h of the partition walls and the short edge width a on the transparent substrate side (that is, the aspect ratio of long side: short side) becomes large, and it is difficult to manufacture the partition walls with high accuracy. there were. In this way, in the configuration in which the partition wall section is simply tapered, the aspect ratio increases as the end width a on the transparent substrate side becomes narrower in order to improve the resolution, and the manufacturing is performed with higher accuracy. As a result, there was a limit to narrowing the partition walls and expanding the display area.

  The present invention has been made in view of the above-described problems, and can easily manufacture a narrowed partition wall with high accuracy, and can enlarge a display area of a transparent substrate, thereby increasing resolution and improving visibility. It is an object of the present invention to provide a charged particle movement type display panel, a method for manufacturing a charged particle movement type display panel, and a charged particle movement type display device.

  In order to achieve the above object, a charged particle migration type display panel according to claim 1 of the present invention includes a transparent substrate, a back substrate disposed opposite to the transparent substrate, and a space between the transparent substrate and the back substrate. A charged particle movement type display panel including a first partition provided on the transparent substrate so as to protrude toward the back substrate side, and protruding toward the transparent substrate side. A second partition provided on the back substrate, wherein a width of at least a joint portion of the first partition with the transparent substrate is narrower than a width of the second partition, and a height of the first partition is high. Is lower than the height of the second partition wall.

  According to such a configuration, the partition wall which has been conventionally single is divided into the first partition wall on the display substrate side and the second partition wall on the back substrate side, so that the heights of the first and second partition walls are increased. Can be lowered respectively. As a result, it is possible to reduce the aspect ratio of both the first and second partition walls. Then, the width of the bonding portion of the first partition wall with the transparent substrate is made narrower than the width of the second partition wall, and the height of the first partition wall is made equal to or less than the height of the second partition wall. The display area can be enlarged to achieve higher resolution and improved visibility. In this case, since the aspect ratio of the first partition wall can be kept small, the narrowed first partition wall can be easily manufactured with high accuracy.

  Here, in the “charged particle movement type display panel”, for example, in addition to an electrophoretic display panel that performs display by moving charged particles contained in a display liquid, display is performed by moving charged particles in a vacuum or gas. The display panel of the structure which performs is included widely. In addition, the “first partition wall” includes a wide variety of embodiments provided on the transparent substrate so as to protrude toward the back substrate side, for example, those protruding toward the back substrate side from the substrate surface of the transparent substrate. Or by projecting toward the back substrate at the same height as the substrate surface by forming a groove on the substrate surface of the transparent substrate.

  Preferably, as in the present invention according to claim 2, it is configured to include particles sandwiched between the convex surface of the first partition wall and the convex surface of the second partition wall, and more preferably, according to claim 3. As in the present invention, the particles sandwiched between the convex surface of the first partition wall and the convex surface of the second partition wall have a dark color.

  According to such a configuration, the black matrix can be easily formed by the particles sandwiched between the convex surface of the first partition wall and the convex surface of the second partition wall, and the step of separately forming the black matrix can be performed. Can be reduced. The particles for forming the black matrix correspond to, for example, black or dark charged particles for black display or dedicated colored particles for forming the black matrix.

  Preferably, as in the present invention according to claim 4, the width of the convex surface of the first partition wall is larger than the diameter of the particles sandwiched between the convex surface of the first partition wall and the convex surface of the second partition wall. Wide configuration. According to such a configuration, it becomes easy to sandwich the particles between the convex surface of the first partition and the convex surface of the second partition, and it is possible to prevent the particles sandwiched at one end from falling off.

  Preferably, as in the present invention according to claim 5, the first partition may have a dark color. According to such a configuration, the first partition itself can be a black matrix, and the black matrix can be formed simultaneously by providing the first partition on the transparent substrate without providing a separate process. .

  In order to achieve the above object, a charged particle movement type display device according to a sixth aspect of the present invention includes any one of the above-described charged particle movement type display panels according to the present invention.

  In order to achieve the above object, a charged particle migration type display panel manufacturing method according to claim 7 of the present invention includes a transparent substrate, a back substrate disposed opposite to the transparent substrate, the transparent substrate, and the back substrate. A charged particle movement type display panel comprising a charged particle encapsulated between the substrates, a first partition forming step of providing a first partition protruding on the transparent substrate on the transparent substrate, A second partition wall forming step of providing a second partition wall projecting toward the transparent substrate on the back substrate, wherein in the first partition wall forming step, at least a width of a bonding portion between the first partition wall and the transparent substrate is set. The width of the second partition is narrower, and the height of the first partition is lower than the height of the second partition.

  According to such a method, similarly to the above, it is possible to reduce the aspect ratio by reducing the height of the first and second partition walls. Then, the width of the bonding portion of the first partition wall with the transparent substrate is made narrower than the width of the second partition wall, and the height of the first partition wall is made equal to or less than the height of the second partition wall. The display area can be enlarged to achieve higher resolution and improved visibility. In this case, since the aspect ratio of the first partition wall can be kept small, the narrowed first partition wall can be easily manufactured with high accuracy.

  Preferably, as in the present invention according to claim 8, it may further include a particle sandwiching step of sandwiching particles between the convex surface of the first partition wall and the convex surface of the second partition wall. More preferably, as in the present invention according to claim 9, in the particle sandwiching step, the particles sandwiched between the convex surface of the first partition and the convex surface of the second partition are dark.

  According to such a method, the black matrix can be easily formed by the particles sandwiched between the convex surface of the first partition wall and the convex surface of the second partition wall as described above. The process of forming can be reduced.

  Preferably, as in the present invention according to claim 10, the method further includes a particle adhesion step of charging the particles and adhering to the convex surface of the first partition wall of the transparent substrate before the particle clamping step. .

  According to such a method, for example, when the transparent substrate is fixed to the back substrate, an electric field is generated to cause the dark charged particles to adhere to the transparent substrate (that is, display black). Dark charged particles can be adhered to the convex surface of the first partition. In the subsequent particle sandwiching step, it is possible to efficiently form a black matrix by sandwiching the dark charged particles between the convex surface of the first partition wall and the convex surface of the second partition wall. For convenience of explanation, the dark-colored charged particles are illustrated, but the particles for forming the black matrix are not limited to this, and can be charged and improve image visibility as a black matrix. A wide range of particles that can be used.

  Preferably, as in the present invention according to claim 11, in the first partition formation step, the width of the convex surface of the first partition is sandwiched between the convex surface of the first partition and the convex surface of the second partition. The diameter is larger than the diameter of the particles. According to such a method, similarly to the above, it becomes easy to sandwich the particles between the convex surface of the first partition wall and the convex surface of the second partition wall, and it is possible to prevent the particles sandwiched at one end from falling off. It becomes.

  Preferably, as in the present invention according to claim 12, in the first partition formation step, the first partition may be dark. According to such a method, as described above, the first partition itself can be made into a black matrix, and the black matrix can be formed simultaneously by providing the first partition on the transparent substrate without providing a separate process. Will be.

  In order to achieve the above object, a charged particle migration type display panel according to a thirteenth aspect of the present invention is manufactured by any one of the above-described methods according to the present invention. In order to achieve the above object, a charged particle migration type display device according to claim 14 of the present invention comprises the above-described charged particle migration type display panel according to the present invention.

  According to the charged particle movement type display panel, the charged particle movement type display panel manufacturing method, and the charged particle movement type display device of the present invention, the narrowed partition wall can be easily manufactured with high accuracy and the display of the transparent substrate It is possible to enlarge the area, and to increase the resolution and improve the visibility.

  Hereinafter, a charged particle migration type display panel and a manufacturing method thereof according to an embodiment of the present invention will be described with reference to the drawings.

<Charged Particle Movement Display Panel According to First Embodiment>
First, an outline of the charged particle migration type display panel according to the first embodiment of the present invention will be described with reference to FIG. 1 and FIG. FIG. 1 is a side sectional view schematically showing a charged particle migration type display panel according to a first embodiment of the present invention. FIG. 2 is an enlarged view of one pixel portion for explaining the configuration of the first and second partitions of the charged particle migration type display panel.

  In FIG. 1, A and A are omitted lines. For convenience of explanation, only a part of the configuration of the charged particle migration type display panel 1 is shown inside the omitted lines A and A. A schematic diagram showing both ends of the charged particle migration type display panel 1 on the outside of A is shown. The charged particle movement type display panel 1 of the present embodiment will be described on the assumption that the region between the transparent substrate 10 and the back substrate 20 is partitioned for each pixel by the first and second partition walls 31 and 32. The charged particle migration type display panel 1 has an overall configuration in which a large number of configurations for one pixel as shown on the inside of the abbreviation lines A and A are continuously arranged in a matrix.

  FIG. 2 conceptually shows various aspects of the first and second partition walls 31 and 32, which are characteristic parts of the charged particle migration type display panel 1, with reference to the omitted line in the middle part. The first and second partition walls 31 and 32 having different configurations on the left and right are illustrated. Actually, the grid-like first and second partition walls 31 and 32 all have the same configuration (including manufacturing errors).

<< Overall Configuration of Charged Particle Movement Display Panel 1 >>
Referring to FIG. 1, a charged particle migration type display panel 1 includes a transparent transparent substrate 10 provided on the display side (upper side in the figure), and a rear substrate disposed substantially in parallel with the transparent substrate 10 at a predetermined interval. 20. A common electrode 11 formed of a transparent member is attached to the back surface of the transparent substrate 10, and a plurality of pixel electrodes 21 provided for each pixel are attached to the surface of the back substrate 20 opposite to the common electrode 11. is there. The common electrode 11 is formed on the transparent substrate 10 so as to face the pixel electrodes 21 in common.

  In the present embodiment, a grid-shaped first partition wall 31 is provided on the common electrode 11 of the transparent substrate 10 so as to protrude toward the back substrate 20 side. A grid-like second partition wall 32 is provided on the surface of the back substrate 20 so as to face the first partition wall 31 so as to protrude toward the transparent substrate 10. The first and second partition walls 31 and 32 will be described in detail later with reference to FIG.

  The space between the transparent substrate 10 and the back substrate 20 in the charged particle migration type display panel 1 is partitioned for each pixel by the first and second partition walls 31 and 32. And the structure for one pixel divided by these transparent substrate 10, the back substrate 20, and the 1st and 2nd partition 31 and 32 is the whole continuous structure in matrix form.

  Further, in the region defined by the transparent substrate 10, the back substrate 20, and the first and second partition walls 31 and 32, black charged particles (dark colored charged particles) 41 and white charged particles (light colored charged particles) 42 are included. The display liquid 40 is filled. In the present embodiment, some black charged particles 41 are sandwiched between the first partition wall 31 and the second partition wall 32 to form the black matrix 41B. Further, the display liquid 40 is hermetically sealed by fixing the ends of the transparent substrate 10 and the back substrate 20 with a sealing agent 50 such as an ultraviolet curable resin.

  Here, the transparent substrate 10 is formed of a material having high transparency and high insulation, and for example, polyethylene naphthalate, polyethersulfone, polyimide, polyethylene terephthalate, glass, or the like can be used. The common electrode 11 is formed of a material having high transparency and can be used as an electrode. For example, tin oxide doped with indium, which is a metal oxide, or tin oxide doped with fluorine. Indium-doped zinc oxide or the like can be used.

  The back substrate 20 is made of a highly insulating material, and for example, an organic material such as glass or polyethylene terephthalate, an insulating metal foil, or the like can be used. Unlike the transparent substrate 10, the back substrate 20 may be transparent or opaque. The pixel electrode 21 is formed of a material having high electrical conductivity such as gold or copper material. A more detailed description of the pixel electrode 21 will be described later with reference to FIG.

  The 1st and 2nd partition 31 and 32 can be formed with the insulating material of an organic compound or an inorganic compound. In the present embodiment, the first and second partition walls 31 and 32 are provided separately and independently from the transparent substrate 10 and the back substrate 20, respectively, but are not limited thereto. The first and second partition walls 31 and 32 may be integrally formed on the back side of the transparent substrate 10 and the front side of the back substrate 20, respectively.

  In the present embodiment, each pixel is partitioned by the first and second partition walls 31 and 32. However, a predetermined number of pixels may be partitioned together. However, when the former configuration is adopted, the gradation is clearly shown for each pixel, and this is coupled with the formation of the black matrix 41B between the first partition wall 31 and the second partition wall 32. The image visibility of the charged particle movement type display panel 1 becomes better.

  As the display liquid 40, a mixed liquid of a highly insulating solution such as hydrocarbon and silicone oil, and a dispersant such as a surfactant and alcohol can be used as a dispersion medium. In addition to the solution, vacuum or gas, for example, nitrogen or air with adjusted humidity can be used. The black charged particles 41 and the white charged particles 42 must be chargeable in the display liquid 40, for example, pigments or dyes made of organic compounds or inorganic compounds, or pigments or dyes containing synthetic resins. Can be used. Further, the black charged particles 41 and the white charged particles 42 are charged with positive or negative polarities different from each other. The charged particles 41 and 42 included in the display liquid 40 are not limited to black and white, and dark charged particles other than black and light charged particles other than white can also be used. However, from the viewpoint of forming the black matrix 41B with charged particles, it is desirable to use the black charged particles 41.

<< About the 1st and 2nd partition walls 31 and 32 >>
In FIG. 2, both the first and second partition walls 31 and 32 in the present embodiment have a rectangular shape with uniform lateral widths L1 and L2 and heights H1 and H2, respectively. Conventionally, a single partition wall is divided into a first partition wall 31 and a second partition wall 32 so that the heights H1 and H2 of each of the first and second partition walls 31 and 32 are reduced to reduce the aspect ratio. Is kept small. That is, the horizontal width L1: height H1 is suppressed in the first partition 31, and the horizontal width L2: height H2 is suppressed small in the second partition 32.

  In addition, the lateral width L1 of the first partition is made narrower than the lateral width L2 of the second partition, and the height H1 of the first partition is made lower than the height of the second partition H2. By narrowing the lateral width L1 of the first partition wall 31, the display area of the transparent substrate 10 can be expanded, and high resolution and visibility can be improved. For example, the width L1 is made narrower than the width L2 of the second partition wall 32 as in the first partition wall 31 shown on the left side of FIG. 2, and the display area corresponding to one or two charged particle diameters D is enlarged. be able to. Actually, as shown on the right side of FIG. 2, the display area is enlarged uniformly on both sides of the first partition wall 31. In practice, it is possible to enlarge the display area exceeding the diameter D of the charged particles D by two.

  As described above, the horizontal width L1 of the first partition wall 31 in FIG. 2 is an example for easy understanding of the present invention, and the display area of the transparent substrate 10 can be enlarged as the horizontal width L1 is reduced. However, in this embodiment, since the black matrix 41B is formed by sandwiching the black charged particles 41 between the first partition wall 31 and the second partition wall 32, the width of the convex surface 31a of the first partition wall 31 (= horizontal width). It is preferable to make L1) wider than the diameter D of the black charged particles 41. As described above, when L1> D, the black charged particles 41 are easily sandwiched between the convex surface 31a of the first partition wall 31 and the convex surface 32a of the second partition wall 32, and the black charged particles 41 sandwiched at one end. Can be prevented from falling off.

  On the other hand, by reducing the height H1 of the first partition wall 31, the aspect ratio with the lateral width L1 described above can be kept small, and it is easy to manufacture with high precision even when the first partition wall 31 is miniaturized as a whole. Become. However, in order to enlarge the display area of the transparent substrate 10, the size is such that the black or white charged particles 41 and 42 can smoothly enter and exit between the back surface of the transparent substrate 10 and the convex surface 32 a of the second partition wall 32. It is necessary to secure a gap. In this embodiment, since the black charged particles 41 are sandwiched between the first partition wall 31 and the second partition wall 32 to form the black matrix 41B, the back surface of the transparent substrate 10 and the convex surface 32a of the second partition wall 32 are formed. Since the same gap as the diameter D of the black charged particles 41 is always ensured between them, the black or white charged particles 41 and 42 can smoothly enter and exit by adjusting the height H1 of the first partition wall 31. And it is sufficient.

<< Example >>
Hereinafter, specific dimensions of each part of the first and second partition walls 31 and 32 shown in FIG. 2 are, for example, the lateral width L1 = 5 μm of the first partition wall 31, the height H1 = 2 μm of the first partition wall 31, and the second partition wall. The lateral width L2 of 32 is 20 μm, the height H2 of the second partition 32 is 18 μm, the diameter D of the charged particles 41 or 42 is 5 μm, and the distance L3 between the centers of the second partitions 32 and 32 partitioning one pixel is 200 μm. It is possible.

<Charged Particle Movement Display Panel According to Second Embodiment>
Next, a charged particle migration type display panel according to a second embodiment of the present invention will be described with reference to FIG. FIG. 3 is an enlarged view of one pixel portion for explaining the configuration of the first and second partition walls of the charged particle migration type display panel according to the second embodiment of the present invention.

  Similar to FIG. 2 described above, FIG. 3 also conceptually shows various aspects of the first and second partition walls 31 and 32, and the first and second partitions having different configurations on the left and right with reference to the omitted line of the intermediate portion. The 1st and 2nd partition 31 and 32 are illustrated, respectively. Actually, the grid-like first and second partition walls 31 and 32 all have the same configuration (including manufacturing errors).

  The charged particle migration type display panel 2 according to the present embodiment has a configuration in which the first partition wall 31 is colored in a dark color, for example, black to form a black matrix 31B. Unlike the first embodiment described above, since the black charged particles 41 are not sandwiched between the first partition wall 31 and the second partition wall 32, the height H1 of the first partition wall 31 is set to black or white charging. The diameter of the particles 41 and 42 is higher than the diameter D of the transparent substrate 10, and the gap between the back surface of the transparent substrate 10 and the convex surface 32a of the second partition wall 32 is secured so that the black or white charged particles 41 and 42 can smoothly enter and exit. There is a need to.

  According to such a configuration, the first partition wall 31 itself can be used as the black matrix 31B, and the black matrix 31B can be simultaneously formed by providing the first partition wall 31 on the transparent substrate 10 without providing a separate process. Will be.

<Charged Particle Movement Display Panel According to Third and Fourth Embodiments>
The present invention is not limited to the configuration of the charged particle migration type display panels 1 and 2 according to the first and second embodiments described above. For example, the first and second partition walls 31 and 32 may be configured as shown in FIG. FIG. 4A is a partially enlarged view showing the configuration of the first and second partition walls of the charged particle migration type display panel 3 according to the third embodiment of the present invention, and FIG. 4B is a fourth view of the present invention. It is the elements on larger scale which show the structure of the 1st and 2nd partition of the charged particle movement type display panel 7 which concerns on embodiment.

  First, in FIG. 4A, each of the first and second partition walls 31 and 32 may have a substantially tapered cross section (trapezoidal shape) as in the prior art. That is, in the above embodiment, the first partition wall 31 has a rectangular cross section with a uniform lateral width L1, but in order to expand the display area of the transparent substrate 10, at least a joint portion of the first partition wall 31 with the transparent substrate 10 is used. The width L1 of 31b may be narrow, and the first partition wall 31 may have a substantially tapered shape in section such that the width L1 of the joint portion 31b <the width L4 of the convex surface 31a.

  As described above, when the width L1 of the joint portion 31b in the first partition wall 31 is smaller than the width L4 of the convex surface 31a, the convex region is formed while the display area of the transparent substrate 10 is expanded by narrowing the width L1 of the joint portion 31b. By making the width L4 of 31a wider than the diameter D of the black charged particles 41 (black matrix 41B), the black matrix 41B can be formed more stably.

  Further, even when the first partition wall 31 has a substantially tapered cross section, the height H1 is low, so that the aspect ratio can be kept small, and an improvement in accuracy in manufacturing the first partition wall 31 can be expected.

  Although not contributing to the expansion of the display area of the transparent substrate 10, the second partition 32 may have a substantially tapered cross section, where the width L2 of the joint portion 32b of the second partition 32> the width L5 of the convex surface 32a. Also in this case, similarly to the above, the height H2 of the second partition wall 32 is low, so that the aspect ratio can be kept small, and the second partition wall 32 can be manufactured easily and accurately.

  Next, in FIG. 4B, the first partition wall 31 is not limited to the one that protrudes toward the back substrate 20 rather than the substrate surface of the transparent substrate 10 as in the first to third embodiments described above. For example, two parallel sectional substantially V-shaped or substantially concave grooves 10a and 10a are formed on the back surface of the transparent substrate 10 by etching or the like, and the same height as the substrate surface of the transparent substrate 10 is formed between the grooves 10a and 10a. Now, a first partition wall 31 protruding toward the back substrate 20 may be provided. For example, after providing the first partition wall 31, the common electrode 11 is formed on the back surface of the transparent substrate 10 by masking the first partition wall 31.

  According to such a configuration, the display area of the transparent substrate 10 can be expanded by forming the grooves 10a and 10a, and the height H1 of the first partition 31 can be reduced to reduce the aspect ratio. Is possible. Further, the height H2 of the second partition wall 32 is reduced by the diameter of the black matrix 41B, and the aspect ratio can be kept small by increasing the lateral width L2 to some extent.

<Display Principle of Charged Particle Movement Type Display Panel>
Next, the display principle of the present charged particle movement type display panel 1, 2, 3, 7 will be briefly described. In FIG. 1, if the black charged particles 41 are positive and the white charged particles 42 are negatively charged, a predetermined voltage is applied to the pixel electrode 21 with the potential on the transparent substrate 10 side as a reference potential. When the back substrate 20 side is made positive, the black charged particles 41 are distributed in the vicinity of the transparent substrate 10, and the white charged particles 42 are distributed in the vicinity of the back substrate 20, and black is displayed on the transparent substrate 10. .

  Further, when the potential on the transparent substrate 10 side is set as a reference potential and a predetermined voltage is applied to the pixel electrode 21 to make the back substrate 20 negative, the black charged particles 41 are distributed in the vicinity of the back substrate 20 and white. The charged particles 42 are distributed in the vicinity of the transparent substrate 10, and white is displayed on the transparent substrate 10.

  Furthermore, the potential on the transparent substrate 10 side is set as the reference potential, and the magnitude and application time of the voltage applied to the pixel electrode 21 are adjusted, so that the black charged particles 41 and the white charged particles 42 are transferred between the transparent substrate 10 and the back substrate 20. When positioned in the vicinity of the intermediate position, since both the black charged particles 41 and the white charged particles 42 can be visually recognized from the transparent substrate 10 side, the display is gray. In this case, by adjusting the voltage applied to the pixel electrode 21 and the application time, the distribution degree of each of the charged particles 41 and 42 is changed, and a gradation having a desired density such as dark gray or light gray is obtained. Can be displayed.

  Based on the principle as described above, a predetermined voltage is applied to the pixel electrode 21 to control the electric field between the transparent substrate 10 side and the back substrate 20 side, thereby moving the charged particles 41 and 42. The gradation for each pixel can be changed. That is, the display can be rewritten.

<Circuit configuration of charged particle migration type display panel>
Next, the circuit configuration of the above-described charged particle movement type display panels 1, 2, 3, and 7 will be described with reference to FIG. FIG. 5 is a circuit configuration diagram showing a drive circuit for the charged particle migration type display panels 1, 2, 3, and 7 according to the first to fourth embodiments.

  In FIG. 5, the drive circuit 4 of the present charged particle movement type display panel 1, 2, 3, 7 is mounted on a location that does not hinder the visibility of the transparent substrate 10, for example, the back substrate 20 shown in FIG. 1. As described above, in the charged particle migration type display panel 1, the pixel electrode 21 is provided for each pixel in a matrix, and each pixel electrode 21 has a thin film transistor 60 (hereinafter referred to as “TFT”). ) Are connected to each other. Each TFT 60 functions as a switching element, and is disposed in the vicinity of the intersection of a plurality of gate lines 71 and source lines 72 parallel to each other. The gate 61 of each TFT 60 is connected to the gate line 71, and the drain 62 of each TFT 60 is connected to the source line 72.

  The control device 80 includes a gate pulse applying unit (hereinafter referred to as “gate driver”) 81 and a source pulse applying unit (hereinafter referred to as “source driver”) 82. The gate driver 81 is connected to the plurality of gate lines 71 described above, and the source driver 82 is connected to the plurality of source lines 72 described above.

  Further, the control device 80 includes a host control unit 83 and a controller unit 84. Although not shown in the figure, the host control unit 83 includes, as a hardware configuration, a CPU that performs main control of the charged particle migration type display panels 1, 2, 3, and 7, a ROM that stores a control program, flags, and data. And a timing generator for generating a timing signal for controlling image rewriting.

  On the other hand, the controller unit 84 is provided with various control means for controlling the gate driver 81 and the source driver 82 based on an instruction from the host control unit 83. The hardware configuration includes IPD, ROM, RAM and the like are included. The host control unit 83 not only controls the charged particle movement type display panels 1 to 3, but also performs an image rewrite instruction to the controller unit 84, transmission of image data before and after the rewrite, and the like.

  In the drive circuit 4 configured as described above, when a turn-off voltage is applied from the gate driver 81 to the gate line 71, all the TFTs 60 connected to the gate line 71 are turned off. On the other hand, when a turn-on voltage is applied from the gate driver 81 to the gate line 71, all the TFTs 60 connected to the gate line 71 are turned on. In this way, the on / off control of the TFT 60 is performed by controlling the voltage applied to the gate line 71.

  When a positive voltage is applied from the source driver 82 to the source line 72 connected to the TFT 60 that is turned on, a positive voltage is applied to the pixel electrode 21 connected to the TFT 60. On the other hand, when a negative voltage is applied from the source driver 82, a negative voltage is applied to the pixel electrode 21 connected to the TFT 60.

  Therefore, by applying a predetermined pulse voltage to the gate line 71 and the source line 72 from the gate driver 81 and the source driver 82 at the same timing, it is possible to apply a predetermined voltage to each pixel electrode 21. Further, since a common voltage (for example, 0 V) for each pixel is applied to the common electrode 11 of the transparent substrate 10, an electric field is generated between the pixel electrode 21 and the common electrode 11, and the black charged particles 41 and the white charged particles are charged. The particles 42 can be moved. As described above, the image is displayed by controlling the gradation of each pixel independently, or the display is rewritten.

<Effects>
As described above, according to the charged particle migration type display panels 1, 2, 3, and 7 of the present embodiment, the single partition wall is conventionally divided into the first partition wall 31 on the display substrate 10 side and the back substrate 20 side. By dividing the first partition wall 32 into the second partition walls 32, the heights H1 and H2 of the first and second partition walls 31 and 32 can be reduced. Thereby, the aspect ratio of both the first and second partition walls 31 and 32 can be kept small. Then, the lateral width L1 of the first partition wall 31 is made narrower than the lateral width L2 (or L5) of the second partition wall 32, and the height H1 of the first partition wall 31 is made equal to or less than the height H2 of the second partition wall 32. As a result, the display area of the transparent substrate 10 can be expanded to achieve higher resolution and improved visibility. In this case, since the aspect ratio of the first partition wall 31 can be kept small, the narrowed first partition wall 31 can be easily manufactured with high accuracy.

  Further, the black matrix 41B or 31B can be easily formed by the black charged particles 41 sandwiched between the convex surface 31a of the first partition wall 31 and the convex surface 32a of the second partition wall 32, or the first partition wall 31 colored black. Therefore, it is possible to reduce the step of forming a black matrix separately.

<Method for Manufacturing Charged Particle Movement Type Display Panel>
Hereinafter, a method for manufacturing the above-described charged particle migration type display panel 1 will be described with reference to FIGS. 6 and 7A to 7G.

  FIG. 6 is a flowchart showing each step of the manufacturing method of the charged particle migration type display panel according to the first embodiment. FIGS. 7A to 7G are schematic views showing respective steps of the method for manufacturing the charged particle migration type display panel according to the first embodiment.

  First, in step S1 of FIG. 6, the first and second partition forming steps are performed. FIG. 7A shows the first partition formation step, and FIG. 7B shows the second partition formation step. In the first barrier rib forming step shown in FIG. 7A, the first barrier rib 31 is provided on the common electrode 11 of the transparent substrate 10. On the other hand, in the second partition formation step shown in FIG. 7B, the second partition 32 is provided so as to partition each pixel electrode 21 of the rear substrate 20.

  The first and second partition walls 31 and 32 may be formed by, for example, applying a photosensitive resist made of an insulating material such as an organic compound or an inorganic compound to the transparent substrate 10 or the back substrate 20 using a spin coater, or a dry film resist. Can be formed by a method of laminating, overlaying a mask pattern on a dry film resist, exposing the mask pattern, and developing with a developer. Using such a method, the lateral width L1 of the first partition 31 is made narrower than the lateral width L2 of the second partition 32, and the height H1 of the first partition 31 is made equal to or less than the height H2 of the second partition 32. ing.

  Subsequently, it progresses to step S2 of FIG. 6, and a sealing agent application | coating process is performed. In this sealing agent application step, as shown in FIG. 7C, a sealing agent 50 such as an ultraviolet curable resin is applied along the peripheral edge of the back substrate 20. Thereby, the side wall which consists of the sealing agent 50 before hardening on the four sides of the back substrate 20 is formed.

  Here, in the present embodiment, the height D of the charged particles 41 and 42 is equal to the total height H1 + H2 of the first and second partition walls 31 and 32 (see FIG. 2). (See FIG. 2), the size of the charged particles 41 and 42 is increased between the first partition wall 31 and the second partition wall 32 facing each other in the substrate facing arrangement step of step S4 to be described later. A gap having a diameter D or more is formed.

  Next, the process proceeds to step S3 in FIG. 6 to perform a display liquid supply process. In this display liquid supply step, as shown in FIG. 7D, the injection nozzle 5 is disposed in a region partitioned by the second partition wall 32 on the pixel electrode 21, and the black and white charged particles 41 are discharged from the injection nozzle 5. , 42 is supplied. The display liquid 40 is prevented from flowing out of the back substrate 20 by the sealant 50 applied on the peripheral edge of the back substrate 20.

  Next, the process proceeds to step S4 in FIG. 6 to perform a substrate facing arrangement process. In the substrate facing arrangement step, as shown in FIG. 7E, the transparent substrate 10 (see FIG. 7A) that has undergone the first partition forming step is used as the back substrate 20 that has undergone the display liquid supply step (see FIG. 7E). d) is disposed so as to be opposed to each other above, and the first partition wall 31 and the second partition wall 32 are opposed to each other. By setting the height of the sealant 50 before curing, a gap larger than the diameter D of the charged particles 41 and 42 is formed between the first partition wall 31 and the second partition wall 32.

  Subsequently, it progresses to step S5 of FIG. 6, and a particle adhesion process is performed. In this particle adhering step, as shown in FIG. 7 (f), a voltage application circuit 6 is connected to the common electrode 11 of the transparent substrate 10 to apply a predetermined voltage, and the black charged particles 41 are generated by the electric field generated thereby. Then, it is attached to the common electrode 11 of the transparent substrate 10. That is, the charged particle movement type display panel 1 in the manufacturing process is displayed in black. In this embodiment, since the black charged particles 41 are positively charged, the black charged particles 41 are attached to the common electrode 11 by making the common electrode 11 negative with the potential on the back substrate 20 side as the reference potential. It can be displayed in black.

  Thereby, the black charged particles 41 enter the gap between the first partition wall 31 and the second partition wall 32, and the black charged particles 41 are formed on the convex surface 31a (see FIG. 2) of the first partition wall 31 protruding on the common electrode 11. To be attached. Although the first partition wall 31 is formed of an insulating material, the height (thickness) H1 is a minute protrusion having a thickness of about 2 μm. The particles 41 can be attached to the convex surface 31 a of the first partition wall 31.

  Thereafter, while maintaining the voltage application to the common electrode 11 by the voltage application circuit 6 described above, the process proceeds to step S6 in FIG. 6 to perform a fixing step (including a particle clamping step). In this fixing step, as shown in FIG. 7G, the sealing agent 50 is cured by ultraviolet irradiation while pressing the transparent substrate 10 toward the back substrate 20 side. In the course of this fixing step, the black charged particles 41 adhered to the convex surface 31a of the first partition wall 31 are sandwiched between the convex surface 31a and the convex surface 32a (see FIG. 2) of the second partition wall 32 opposite thereto. Then, a grid-like black matrix 41B is formed along the first and second partition walls 31 and 32 (see an enlarged view in FIG. 5G).

<Effects>
As described above, according to the manufacturing method of the charged particle migration type display panel 1 of the present embodiment, when the transparent substrate 10 and the back substrate 20 that are arranged to face each other are fixed, only a predetermined electric field is generated. The black charged particles 41 can be easily attached to the convex surfaces 31a of the first partition walls 31, and the black charged particles 41 are interposed between the convex surfaces 31a and 32a of the first and second partition walls 31 and 32 in the subsequent fixing step. Thus, the black matrix 41B can be formed efficiently.

  Further, not only in the particle attaching step but also in the fixing step, the black charged particles 41 can be attached to the convex surface 31 a of the first partition wall 31, and the black charged particles 41 along the first and second partition walls 31 and 32. The lattice-like black matrix 41B made of can be formed with high accuracy.

  Furthermore, since the black charged particles 41 can be efficiently attached to the convex surface 31a of the first partition wall 31 without using a conventional mask, the number of manufacturing steps can be greatly reduced as compared with the conventional manufacturing method. It is possible to cope with the manufacture of a large display panel.

1 is a side cross-sectional view schematically showing a charged particle migration type display panel according to a first embodiment of the present invention. It is an enlarged view of one pixel part for demonstrating the structure of the 1st and 2nd partition of the charged particle movement type | mold display panel which concerns on the said 1st Embodiment. FIG. 6 is an enlarged view of one pixel portion for explaining a configuration of first and second partitions of a charged particle migration type display panel according to a second embodiment of the present invention. FIG. 4A is a partially enlarged view showing the configuration of the first and second partition walls of the charged particle migration type display panel according to the third embodiment of the present invention, and FIG. 4B is the fourth embodiment of the present invention. It is the elements on larger scale which show the structure of the 1st and 2nd partition of the charged particle movement type display panel which concerns on a form. It is a circuit block diagram which shows the drive circuit of the charged particle movement type | mold display panel which concerns on the said 1st-4th embodiment. It is a flowchart which shows each process of the manufacturing method of the charged particle movement type | mold display panel which concerns on the said 1st Embodiment. FIGS. 4A to 4G are schematic views showing respective steps of the method for manufacturing a charged particle migration type display panel according to the first embodiment.

Explanation of symbols

1, 2, 3, 7 Charged particle movement type display panel 10 Transparent substrate 11 Common electrode 20 Back substrate 21 Pixel electrode 31 First partition 32 Second partition 31a, 32a Convex surface 31b, 32b Joined portion 31B, 41B Black matrix 40 Display liquid 41 Black charged particles (Dark colored particles)
42 White charged particles (light colored charged particles)
50 Sealant 60 Thin film transistor (TFT)
61 Gate 62 Drain 71 Gate line 72 Source line 80 Controller 81 Gate driver (gate pulse applying means)
82 Source driver (source pulse application means)
83 Host control unit 84 Controller unit 4 Drive circuit 5 Injection nozzle 6 Voltage application circuit

Claims (14)

A charged particle movement type display panel comprising: a transparent substrate; a back substrate disposed opposite to the transparent substrate; and charged particles sealed between the transparent substrate and the back substrate.
A first partition provided on the transparent substrate so as to protrude toward the back substrate;
A second partition provided on the back substrate so as to protrude toward the transparent substrate,
The width of at least the junction of the first partition with the transparent substrate is narrower than the width of the second partition, and the height of the first partition is lower than the height of the second partition. Charged particle movement type display panel.   2. The charged particle movement type display panel according to claim 1, further comprising particles sandwiched between the convex surface of the first partition wall and the convex surface of the second partition wall.   3. The charged particle migration type display panel according to claim 2, wherein the particles sandwiched between the convex surface of the first partition and the convex surface of the second partition are dark.   4. The charging according to claim 2, wherein a width of the convex surface of the first partition wall is wider than a diameter of the particle sandwiched between the convex surface of the first partition wall and the convex surface of the second partition wall. Particle movement type display panel.   The charged particle migration type display panel according to any one of claims 1 to 4, wherein the first partition wall is a dark color.   A charged particle movement type display device comprising the charged particle movement type display panel according to claim 1. A charged particle movement type display panel comprising a transparent substrate, a back substrate disposed opposite to the transparent substrate, and charged particles sealed between the transparent substrate and the back substrate,
A first partition forming step of providing a first partition protruding on the back substrate side on the transparent substrate;
A second partition wall forming step of providing a second partition wall protruding on the transparent substrate side on the back substrate,
In the first partition formation step, the width of at least the junction of the first partition and the transparent substrate is narrower than the width of the second partition, and the height of the first partition is set to the height of the second partition. A method for producing a charged particle migration type display panel, characterized in that it is lower than the height.   8. The method of manufacturing a charged particle migration type display panel according to claim 7, further comprising a particle sandwiching step of sandwiching particles between the convex surface of the first partition wall and the convex surface of the second partition wall.   9. The charged particle migration type display panel according to claim 8, wherein, in the particle sandwiching step, the particles to be sandwiched between the convex surface of the first partition and the convex surface of the second partition are dark. Method.   The charged particle movement display according to claim 8 or 9, further comprising a particle adhesion step of charging the particles to adhere to the convex surface of the first partition wall of the transparent substrate before the particle clamping step. Panel manufacturing method.   In the first partition formation step, the width of the convex surface of the first partition is made wider than the diameter of the particles sandwiched between the convex surface of the first partition and the convex surface of the second partition. The manufacturing method of the charged particle movement type | mold display panel in any one of Claims 8-10.   The method for manufacturing a charged particle migration type display panel according to claim 8, wherein in the first partition formation step, the first partition is dark.   A charged particle migration type display panel manufactured by the method according to claim 8.   A charged particle movement type display device comprising the charged particle movement type display panel according to claim 13.

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